UITableViewCell Class Reference: “Whether you use a predefined or custom cell, you can change the cell’s background using the backgroundView property or by changing the inherited backgroundColor property. In iOS 7, cells have a white background by default; in earlier versions of iOS, cells inherit the background color of the enclosing table view. If you want to change the background color of a cell, do so in the tableView:willDisplayCell:forRowAtIndexPath: method of your table view delegate.”


- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell
forRowAtIndexPath:(NSIndexPath *)indexPath
    cell.backgroundColor = [UIColor lightGrayColor];